Clinically active bovine growth hormone fraction

ABSTRACT

A clinically active component (TBGH-d) of a tryptic digest of bovine growth hormone (BGH) found to be homogeneous by disc electrophoresis and sedimentation equilibrium and having substantially the same molecular weight and amino acid composition as BGH was separated into two fractions, A-I and AII, by dextran gel filtration in 50% acetic acid. The amino acid analysis of the A-I and A-II fractions accounted for all the amino acids in the TBGH-d. The biological activity of the A-II fraction was found to be about 10-30% of TBGH-d. This fraction, having a molecular weight of about 5000 and an amino acid content or chain length of 38 amino acids, appears to exhibit human growth hormone-like activity. This fraction also appears to have wider applicability than simply being useful for the acceleration of somatic growth in humans. For example, this fraction would appear to have utility in promoting increased function and growth in an impaired liver and in effecting tissue regeneration, such as the promotion of healing of stress ulcers. It would also appear that this fraction has utility in the stimulation of protein synthesis to increase immunological competence and in wound and fracture healing. Also, it would appear that this fraction has utility in non-human applications, e.g., for increasing milk production, for increasing wool production and for accelerating animal growth.

United States Patent [191 Sonenberg et al.

[4 1 Sept. 9, 1975 CLINICALLY ACTIVE BOVINE GROWTH HORMONE FRACTION [75] Inventors: Martin Sonenberg, New York, N.Y.;

Nobuyuki Yamasaki, Matsuyama, Japan [73] Assignee: Research Corporation, New York,

[22] Filed: Mar. 31, 1972 [21] Appl. No.: 240,301

Related US. Application Data [62] Division of Ser. No. 13,162, Feb. 20, 1970, Pat. No.

[52] US. Cl. 424/177; 260/112 R 51 Int. cm A6 1K 37/00 [58] Field of Search 424/177; 260/1 12 [56] References Cited OTHER PUBLICATIONS Sonenberg et al., Ann. N. Y. Acad. Sci. 1968, 148(2) 532558.

Primary ExaminerRichard L. Huff Attorney, Agent, or FirmCooper, Dunham, Clark, Griffin & Moran [57] ABSTRACT A clinically active component (TBGH-d) of a tryptic digest of bovine growth hormone (BGH) found to be homogeneous by disc electrophoresis and sedimentation equilibrium and having substantially the same molecular weight and amino acid composition as BGl-l was separated into two fractions, A-1 and A-ll, by dextran gel filtration in 50% acetic acid. The amino acid analysis of the A-1 and A-II fractions accounted for all the amino acids in the TBGl-l-d. The biological activity of the A-II fraction was found to be about 1030% of TBGH-d. This fraction, having a molecular weight of about 5000 and an amino acid content or chain length of 38 amino acids, appears to exhibit human growth hormone-like activity. This fraction also appears to have wider applicability than simply being useful for the acceleration of somatic growth in humans. For example, this fraction would appear to have utility in promoting increased function and growth in an impaired liver and in effecting tissue regeneration, such as the promotion of healing of stress ulcers. It would also appear that this fraction has utility in the stimulation of protein synthesis to increase immunological competence and in wound and fracture healing. Also, it would appear that this fraction has utility in non-human applications, e.g., for increasing milk production, for increasing wool production and for accelerating animal growth.

2 Claims, No Drawings CLINICALLY ACTIVE BOVINE GROWTH HORMONE FRACTION This is a division of application Ser. No. 13,162 filed Feb. 20, 1970, now US. Pat. No. 3,664,925.

This invention relates to the production of clinically active growth hormone materials, particularly clinically active growth hormone materials derived from bovine growth hormone and the like.

It is known that fractions of tryptic digest of bovine growth hormone have human growth hormone-like activity in hypopituitary humans, see the articles by A. C.

Nadler, M Sonenberg, M. I. New and C. A. Free entitled Growth Hormone Activity in Man with Components of Tryptic Digests of Bovine Growth Hormone in Metabolism 16: No. 9, September, 830-845 (1967) and M. Sonenberg, C. A. Free, J. M. Dellacha, G. Bonadonna, A. Haymowitz and A. C. Nadler entitled The Metabolic Effects in Man of Bovine Growth Hormone Digested with Trypsin in Metabolism 14: No. 11, November, 1189-1213 (1965). Of further interest in connection with the preparation of growth hormone material from various sources including bovine pituitary growth hormone, see US. Pat. Nos. 2,974,088 (1961), 3,118,815 (1964), 3,265,578 (1966), 3,275,516 (1966), 3,306,823 (1967), 3,308,027 (1967) and 3,317,400 (1967). The disclosures of the above-identified publications and patents are herein incorporated and made part of this disclosure.

It is an object of this invention to provide clinically active hormone material derived from an animal source such as bovine growth hormone.

It is another object of this invention to provide a clinically active fraction derived from a tryptic digest of bovine growth hormone and method for producing same.

Another object of this invention is to provide growth hormone material useful for administering to animals and the like.

How these and other objects of this invention are achieved will become apparent in the light of the accompanying disclosure. In accordance with at least one embodiment of the practice of this invention at least one of the foregoing objects will be achieved.

A clinically active component TBGHd of the tryptic digest of bovine growth hormone, homogeneous by sedimentation equilibrium and disc electrophoresis, was separated into two components or fractions, A-1 and A-ll, by dextran gel (Sephadex G-75) filtration in 50% acetic acid. The A-ll fraction having a molecular weight of 5000 was found to possess a biological activity equivalent to -30% of TBGl-l-d.

This fraction made up of 38 amino acids exhibits human growth hormone-like activity as evidenced by a decrease in blood urea nitrogen and urinary nitrogen and an increase in serum inorganic phosphorus when administered to a pituitary dwarf. There was also observed an increase in urinary calcium. When human growth hormone was administered to the same pituitary dwarf the responses were qualitatively the same although the human growth hormone was more effective, as might be expected. This fraction in accordance with this invention evidencing clinical activity was administered by injection into the pituitary dwarf.

The clinically active fraction, the A-II fraction referred to hereinabove, upon analysis was found not to contain a disulfide bond and the amino terminal amino acid was found to be valine and the carboxyl terminal amino acid was found to be arginine.

The data obtained in connection with the preparation of the above-described A-ll clinically active fraction indicate that the homogeneous hormonally active component of the tryptic digest of bovine growth hormone consists of two peptides formed by the cleavage of two peptide bonds at arginine residues within one of the disulfide groups and that these peptide groups are associated under mild conditions.

More particularly, in connection with the preparation of a clinically active fraction, the above-described A-ll fraction in accordance with this invention, the clinically active component TBGHd of the tryptic digest of bovine growth hormone homogeneous by sedimentation equilibrium and disc electrophoresis was separated into two components, A-1 and A-ll, by dextran gel (Sephadex G-) filtration in 50% acetic acid. The molecular weight of the A-l fraction was found to be 16,000 and for the A-Il fraction to be 5,000, as indicated hereinabove. The amino acid analysis of the A-1 and A-ll fractions accounted for the total amino acids in TBGH-d. Two disulfide bonds were found in the A-l fraction and none in the A-ll fraction. Further, the amino terminal amino acids of the A-l fraction were found to be phenylalanine, alanine and serine and for the A-ll fraction the amino terminal amino acid was found to be valine. The carboxyl terminal amino acids of the A-l fraction were phenylalanine and arginine and for the A-ll fraction the carboxyl terminal amino acid was arginine.

The reduced and carboxymethylated A-I fraction gave two fractions by dextran gel filtration. The larger reduced and carboxymethylated peptide had a molecu lar weight of approximately 1 1,000 and contained phenylalanine and alanine as amino terminal residues and arginine as a carboxyl terminal amino acid. The molecular weight of the second reduced and carboxymethylated fraction was found to be approximately 5,000. In this second fraction serine was found to be .the amino terminal amino acid and phenylalanine as the carboxyl terminal amino acid.

In the production of the clinically active All fraction one gram of bovine growth hormone BGl-l gave 920 milligrams of unfractionated tryptic digest of bovine growth hormone (TBGH). From this TBGl-l there was obtained 1 19 milligrams of component a of a tryptic di gest of bovine growth hormone (TBGH-d) found to be clinically active. This amount of TBGl-l-d gave 84 mg. of the above-described A-l fraction and 28 mg. of the above-described clinically active All fraction.

ln the preparation of the clinically active A-ll fraction derived from a clinically active component TBGH- d of a tryptic digest of bovine growth hormone BGl-l, the BGH was prepared by the method of Dellachaand Sonenberg, see J. Biol. Chem. 239, 1515 (1964). The clinically active component TBGH-d was obtained by diethylaminoethyl (DEAE)-cellulose column chromatography of the tryptic digest of BGH as reported in Ann. N. l. Acad. Sci, 148, 532 (1968). In the preparation of the clinically active A-ll fraction by dextran gel filtration the clinically active component TBGH-d of a tryptic digest of bovine growth hormone was added in 50% acetic acid to a column (2.5 X 40 cm.) of dextran gel (Sephadex G75) equilibrated with 50% (v/v) acetic acid at a temperature of 4C., followed by elution with the same solution. Fractions eluted were read at 280 mu and an aliquot of each fraction was taken for further identification by ninhydrin reaction after alkaline hydrolysis, see J. Biol. Chem. 238 622 1963). Fractions were evaporated and then freeze dried and the fractions were further purified by rechromatography. For the study of biological activity fractions ob tained by gel filtration were freeze dried directly from 50% acetic acid. If desired, in the practice of this invention other solvents, such as urea, w'ioxane, dichloroacetic acid and acetic acid of higher or lower concentrations than 50% are useful in the practice of this invention for the preparation of the clinically active fraction.

In the preparation and the analyses of the materials in accordance with this invention, the analytical electrophoresis was carried out on polyacrylamide gel by the disc electrophoretic method of Ornstein, Ann. N. l. Acad. Sci. 121, 321 (1964) and Davis, Arm. N. Y. Acad. Sci. 121, 404 (1964). The electrophoresis was performed at a pH of 9.5 in 7.5% polyacrylamide gel. Protein components were stained with 0.5% amidoschwarz in 7% acetic acid. For the amino acid analysis the proteins or peptides were hydrolyzed in 6N HCl at 1 10C. under reduced pressure for 24 and 72 hours. Hydrolysates were analyzed on an amino acid analyzer according to the method of Spackman, Stein and Moore, Anal. Chem. 30, 1190 (1958) and corrections were applied for amino acids partially destroyed during hydrolysis.

1n the determination of the NH -terminal residues, dinitrophenylation was performed without alcohol, J. Biol. Chem. 213, 487 (1955) at pH 8.6 at 40C. for 3 hours. DNP-protein or -peptide was hydrolyzed by 6N HCl in a sealed evacuated tube at 105C. for 16 hours. Identification and quantitative analysis of DNP-amino acids were performed by two-dimensional thin layer chromatography. Two solvent systems were used, solvent Sl made up of toluene/pyridine/ethylene chlorhydrin/0.8N ammonium hydroxide (100:30:60:60) and solvent S2 made up of benzene/pyridine/acetic acid (80z20z2). The upper phase of solvent S1 was used for chromatography. DNP-spots were eluted with 4 ml. of 1% NaHCO and their absorption read at 360 mu after removing silica gel by centrifugation. Pure DNP-amino acids were hydrolyzed with the samples followed by thin layer chromatography with the same procedure as that employed for DNP derivatives. The Nl-l -terminal amino acid values were corrected for losses during these procedures.

For the determination of the COOH-terminal residues to 0.2 umol of dried samples were added 25 mg. of hydrazine sulfate and the mixture was dried in a vacuum desiccator over P for 3 days. Anhydrous hydrazine (0.2 ml.) was added and allowed to react in a sealed tube at 60 for 16 hours. The hydrazinolysate was dried in a desiccator over concentrated H 50 After treatment with heptanal, J. Bloc-hem. (Tokyo) 68, 475 1958), the hydrazinolysate was dinitrophenylated in 66% ethanol, Biochem. J. 39, 507 1945 and the COOl-l-terminal DNP-amino acid fractionally extracted, J. Bioclzem. (Tokyo) 56, 314 (1964). Quantitative analysis of DNP-amino acids was performed by thin layer chromatography as described above for NIL-terminal amino acids. Appropriate recovery corrections were determined by submitting given amino acids to the hydrazine reaction in the presence of protein.

Total reduction and carboxymethylation of TBGl-l-d or larger fractions obtained by gel filtration in 50% acetic acid were performed by the method of Crestfield et al, J. Biol. Chem. 238, 622 (1963). Fractionation of reduced and carboxymethylated peptides was carried out on a column (2.5 X 40 cm.) of dextran gel (Sephadex G) in 50% acid covered by aluminum foil. Aliquots of each fraction were taken for identification by the ninhydrin reaction. Peptide fractionswere rotary evaporated and then freeze dried.

Molecular weights of TBGH-d fractions separated by gel filtration in 50% acetic acid were determined by sedimentation equilibrium at 410 in a Spinco Model E ultracentrifuge equipped with ultraviolet optics and automatic scanner.

Growth hormone activity of TBGH-d as well as the fractions A-l and A-Il obtained by gel filtration in 50% acetic acid was determined in hypophysectomized rats by the method of Marx, Simpson and Evans, Endocrinology 30, 1 1942) and the weight gain for 10 days was recorded.

In the above mentioned preparation and/or analytical procedures, in the dextran gel filtration of the tryptic digest of bovine growth hormone the pure TBGH-d revealed a single peak on dextran gel Sephadex G75 in 0.1 M carbonate buffer at pH 9.5. In 6 M urea, however, this component was separated into two peaks on Sephadex G75. Upon elution of TBGH-d from the Sephadex G75 column by means of 50% acetic acid the two fractions, A-1 and A-ll, were obtained with increasing elution volume, respectively.

1n these procedures from 1 gm. of BGH the yield was 920 mg. of unfractionated TBGH, 1 19 mg. of homogeneous TBGH-d, 84 mg. of A-1 and 28 mg. of A-ll. Analytic disc electrophoresis revealed two homogeneous components A-1 and A-Il and component A-II had slightly greater anodal mobility than A-l.

In the molecular weight determination by sedimentation equilibrium the molecular weight of the large separated A-l fraction of Sephadex G75 in 50% acetic acid was approximately 16,000 and that of the smaller A-ll component was 5,000.

In the determination of the amino and carboxyl terminal amino acids of components A-1 and A-ll the number of mols of NH -terminal amino acids in component A-l was found to be 0.48 for phenylalanine, 0.44 for alanine and 0.83 for serine per mol of A-l molecular weight of 16,000. Valine was found as the Nl-l terminal amino acid of component A-ll with 0.92 mol per mol of molecular weight of 5,000. Whereas TBGH- d had one phenylalanine and two arginine as the carboxyl terminal amino acids, component A-I had 1 mol of arginine and 1 mol of phenylalanine per molecular weight of 16,000. In contrast 1 mol of arginine was found in component A-Il as a carboxyl terminal amino acid.

In accompanying Table No. l the amino acid analyses of components A-1 and A-ll are presented and compared with those of TBGH-d and BGH.

Glutamic Acid and/or Table No. l-Continued Table No. 3

Amino Acid [30H GpL A4 A4] TBGH Base Uptake Yield Biological Activity Glutamine 49 5 Equivalents/22,000 g USP units/mg s12. Proline 6.1 5.9 5.9 0.9 1 24 94 L39 i 020 Glycine 9.8 10.8 6.5 2.9 129 I Q24 Alanine 13.5 12.6 12.1 1.0 2 24 93 2. 7 i 032 Cysteine (/2) 4.6 4.5 3.9 0 1.68 i 0.33 Valine 6.4 6.8 3.0 3.0 3 2.4 86 1.40 i 0.32 Methionine 4.4 4.2 2.3 1.0 4 2.4 85 1.50 $0.16 lsoleucine 6.5 6.4 5.5 0.9 5 2.4 91 1.88 1' 0.44 Leucine 24.3 23.9 19.5 5.1 6 2.5 98 1.16 1 0.26 Tyrosine 6.0 5.7 4.6 1.0 7 2.5 93 1.79 i 0.32 Phenylalanine l 1.6 l 1.4 9.5 1.8

The resulting digest TBGH, as described herein- The tests of the biological activity of the growth horb e, i th ubjected to fractionation by chromatogmone derivatives or components prepared in accorraphy on diethylaminoethyl cellulose to produce the dance with this invention are set forth in accompanying clinically active component TBGH-d found to be ho- Table No. 2. As indicated by the results reported in acmogeneous by disc electrophoresis and sedimentation companying Table No. 2 only component A-ll preequilibrium. This component TBGH-d is then subpared in accordance with thi i ti h d growth jected to dextran gel filtration to produce the clinically promoting activity. active fraction A-II in accordance with this invention as described hereinabove. Table 2 In the treatment of the pituitary dwarf mentioned V hereinabove with the active A-ll fraction, the treatment Fraction g involved metabolic studies. The pituitary dwarf re g ceived 5 milligrams of the A-II fraction dissolved in TBGH-d I 0.92 10.19 water twice a day intramuscularly for 5 days. The ac- (50% and) tive A-ll fraction could just as well been given intrave- 6 nously although one would predict that the effects would be more prolonged with intramuscular injection. It would appear unlikely that the A-II fraction, being a It was observed that the maller e tide m ent peptide, could efficiently be given orally since it would A-Il obtained from TBGH-d by dextran gel filtration in be dlgested gastrointestinal tract 50% acetic acid has approximately 30% of the biologiother tests mvolvmg the aetwe fmeuon P ca] activity f thE parent material GH It ld pared in accordance with this 1nvent1on were also earpear that the active site of BGH may be present in a ried out. These tests involved studies in connection limited part of the whole protein molecule with isolated rat epidydimal fat pad tissues. The results The Clinically active component made in accordance of these tests indicate that the active A-ll fract1on is with this invention may be administered to a human or 40 comparable m blochemlcal effects to Povme grow th to an animal parenterally, e.g., by intramuscular injechormone and human growth hormone m the same tion sues.

Although emphasis has been placed herein upon the f ti i an example fi g i l fmthfthls preparation of the clinically active material from bog or t e preplmtlon 0 t e acuw vine growth hormone other animal growth hormone material would also appear to be suitable for the prepa- EXAMPLE ratio therefr fa cl' icall active 0 m onent simin Q m p Nine grams of bovine growth hormone prepared by lar to or equivalent to the clmically active material de- I the method of Dellacha and Sonenberg are digested at rived from bovine growth hormone in accordance with 25C. at p 9-5 in an automatic titrator under nitrogen thls other Such sultaple ammal giowth with constant stirring. Purified trypsin is added to this mone mammal would appear to Include pqrcme growth bovine growth hormone which is in tenth molar KCl in hormone mammal and equme growth hormone mate a ratio of enzyme to bovine growth hormone of about 1:300. The digestion is allowed to proceed for about Techmques are known for obtammg a tryptlc dlgest 8-12 minutes during which time two bonds are split. of bovine growth hormone (TBGl-l). In addition to the The reaction mixture is stopped by the addition of an techniques already mentioned other suitable techequivalent amount of Soybean trypsin inhibitor 6g mques are descrlbed m Membdism 1189 (1965) about 3 milligrams, and the reaction mixture is transand Metabolism, 16, 830 (1967). These oth teehferred to dialysis tubing. It is dialyzed exhaustively mques y be p y the preparatlen of TBGH against distilled water and then freeze-dried. From 9 1n the practice of this invention. grains of undigested bovine growth hormone about 8% Prior to the preparation of TBGH the bovine growth grams of a total tryptic dige t of bovine growth horhOrmOne as pr pared by the method demone are obtained. About four grams of the total digest scribed in J. Biol. Chem., 239 1515 1964). After prepare then applied to a DEAE-cellulose column and with aration the BGl-i was then subjected to trypsin digesstepwise elution with ammonium bicarbonate, concention to produce TBGH. The extent of proteolysis, yield and biological activity of the resulting digest TBGH are set forth in accompanying Table No. 3.

trations, 0.03 M, 0.05 M, 0.07 M, 0.1 M and 0.15 M successive fractions are obtained. The 0.05 M fraction generally contains the TBGl-l-d. From 4 grams of the total digest 450 milligrams of TBGH-d are obtained. This is recovered by freeze-drying directly. 200 milligrams of TBGH-d are then applied to a dextran gel (Sephadex G-75) column and developed with 50% acetic acid. Two fractions, A-1 and A-II, are obtained. Both are recovered by freeze-drying directly from the acetic acid solution. From the 450 milligrams of TBGH-d about 100 milligrams of A-II are obtained. The A-ll is then used directly for further chemical and biological studies. For human investigation the material is dissolved in water and acidified to pH 4.5. The A-ll solution is then sterilefiltered through a Swinney filter to give a concentration of 5 milligrams/milliliter. This sterile solution is then used in animal tests for pyrogenicity, sterility and endotoxin contamination.

As will be apparent to those skilled in the art in the light of the foregoing disclosure, many modifications, substitutions and alterations are possible in the practice of this invention without departing from the spirit or scope thereof.

What is claimed is:

l. A composition consisting essentially of the polypeptide obtained from the tryptic digest of bovine growth hormone by diethylaminoethyl-cellulose chromatography to produce therefrom a homogeneous component as evidenced by disc-electrophoresis and sedimentation equilibrium, said component then subjected to dextran gel filtration in the presence of 50% acetic acid to produce said polypeptide, said polypeptide having a molecular weight of about 5,000 and a chain length of about 38 amino acids, the amino acid content of said polypeptide comprising about 2.0 lysine, about 2.8 arginine, about 3.8 aspartic acid and asparagine, about 2.6 threonine, about 1.9 serine, about 4.9 glutamic acid and/or glutamine, about 0.9 proline, about 2.9 glycine, about 1.0 alanine, about 3.0 valine, about 1.0 methionine, about 0.9 isoleucine, about 5.1 leucine, about 1.0 tyrosine, about 1.8 phenylalanine, having valine as the amino terminal amino acid and arginine as the carboxy terminal amino acid, and a carrier, said polypeptide present in said composition at a concentration of about 5 milligrams per milliliter.

2. A method 'of treating pituitary dwarfism in a human which comprises intramuscularly administering to the human the polypeptide of claim 1 in the amount of about 10 milligrams per day. 

1. A COMPOSITION CONSISTING ESSENTIALLY OF THE POLYPEPTIDE OBTAINED FROM THE TRYPTIC DIGEST OF BOVINE GROWTH HORMONE BY DIETHYLAMINOETHYL-CELLULOSE CHROMATOGRAPHY TO PRODUCE THEREFORM A HOMOGENEOUS COMPONENT AS EVIDENCE BY DISCELECTROPHORESIS AND SEDIMENTATION EQUILIBEIUM, SAID COMPONENT THEN SUBJECTED TO DEXTRAAN GEL FILTRATION IN THE PRESENCE OF 50% ACETIC ACID TO PRODUCE SAID POLYPEPTIDE, SAID POLYPEPTIDE HAVING A MOLECULAR WEIGHT OF ABOUT 5,000 AND A CHAIN LENGTH OF ABOUT 3, AMINO ACIDS, THE AMINO ACID CONTENT OF SAID POLYPEPTIDE COMPRISING ABOUT 2.0 LYSNE, ABOUT 2.8 ARGININE, ABOUT 3.8 ASPARTIC ACID AND ASPARAGINE, ABOUT 2.6 THREONINE, ABOUT 1.9 SERINE, ABOUT 4.9 GLUTAMIC ACID AND/OR GLUTAMINE, ABOUT 0.9 PROLINE, ABOUT 2.9 GLYCINE, ABOUT 1.0 ALANINE, ABOUT 3.0 VALINE, ABOUT 1.0 METHIONINE, ABOUT 0.9 ISOLEUCINE, ABOUT 5.1 LEUCINE, ABOUT 1.0 TYROSINE, ABOUT 1.8 PHENYLALANINE, HAVING VALINE AS THE AMINO TEWMINAL AMINO ACID AND ARGININE AS THE CARBOXY TERMINAL AMINO ACID, AND A CARRIER, SAID POLYPEPTIDE PRESENT IN SAID COMPOSITION AT A CONCENTRATION OF ABOUT 5 MILLIGRAMS PER MILLILITER.
 2. A method of treating pituitary dwarfism in a human which comprises intramuscularly administering to the human the polypeptide of claim 1 in the amount of about 10 milligrams per day. 